Conservation usually starts from the idea that nature does best when we leave it alone. Rob Avis thinks that instinct is the problem.

Rob Avis P.Eng. (5th World) · Host: Jackie De Burca

In the first of a two-part series, Jackie De Burca talks to Rob Avis — a mechanical engineer who left the Alberta oil patch to spend the last two decades designing regenerative farms, homesteads and buildings — about beavers, entropy, and why the instinct to keep our hands off nature may be doing more damage than the interference it was meant to prevent.

Rob Avis was clearing forest for oil pipelines when he started doing arithmetic. He worked out roughly how many hours a human life contains — about 600,000 — realised he had spent a third of his, and asked what he wanted to do with the rest. In 2008, with oil at record highs and almost nobody interested in energy descent, he and his wife Michelle left engineering careers worth three hundred thousand dollars a year between them and moved in with her mother.

What he came back with is an argument that cuts against most environmental messaging. Humans are not inherently destructive, he says — we simply lack feedback. We are the first people in history able to see the damage we have done from orbit, and the same capacity that shows us the wreckage is the one we will use to repair it.

The centrepiece of this episode is a creek on his own farm in central Alberta, and the beavers the previous owner used to kill. To an untrained eye they have made a mess: trees down, land flooded. Rob's contention is that they are increasing the complexity of that landscape dramatically — and that the difference between damage and regeneration is not whether you disturb a system, but the scale, timing, placement and form of the disturbance.

From there the conversation widens into a genuine challenge to conservation by exclusion: national parks, Allan Savory's elephant cull, and the wolves of Yellowstone. In the next episode we get into method — how Rob actually designs a property, and what any of this means for roofs, streets and gardens.

00:00Intro — we live amongst our own ruins, and why Rob thinks that's a hopeful fact04:09600,000 hours — the calculation that took two engineers out of the Alberta oil patch10:09Three days of food — how deep a city's supply actually runs13:58Entropy and syntropy — Howard Odum, and how the Fertile Crescent became a desert14:55Energy slaves — the hidden labour inside a barrel of oil16:27The beavers on his creek — eight to ten families, and the owner who used to kill them17:18Vermin and invasive — judgements dressed as descriptions, and the 28-fold claim20:19The problem with national parks — Rob's case against conservation by exclusion22:57Allan Savory's elephants — a cull, and the land that degraded anyway23:49Yellowstone's wolves — what happened when the predators came back28:10Why bad news doesn't move people — the amygdala problem in environmental messaging28:51The canoe — look at the rock and you hit the rock33:39Who actually comes to this work — fear as an entry point, and why it's a poor place to stay35:34“It's the climate between our ears” — the problems are social, not technical36:33A Rosa Parks moment — why change never comes from the majority37:21Outro — Jackie on what Part 2 answers

Mechanical engineer, P.Eng. · Co-lead, 5th World

Rob Avis, P.Eng., is a mechanical engineer who left oil and gas in 2008 to learn how land could be managed better. He co-leads 5...

Professor Theodore Hanein · Lei Zhang · Anna Simmons · Cecilia Pesce (earth4Earth) · Host: Jackie De BurcaRelease

Jackie De Burca spends this episode inside one company. earth4Earth makes bricks out of soil dug from building sites, bound with a lime its co-founder worked out how to make at room temperature — by accident, on a day the lab furnace wouldn't switch on. Four of the people behind it explain what they have built, what the industry says back to them, and why the most interesting question about a brick might be what happens to it at the end.

In 2017, Professor Theodore Hanein went into a laboratory to heat a material and found the furnace broken. He mixed it cold instead, ran the characterisation anyway, and got results good enough to keep. What he had stumbled into was a way of producing lime — one of the most widely used bulk materials on earth — without the roughly 900°C kiln the process has needed since antiquity. He did not publish until 2021, and an attempt to patent it was turned down.

That binder is now in a brick. The bricks are made from soil excavated at construction sites that would otherwise be landfilled, mixed with the lime-based binder, and compressed rather than fired. Because the lime carbonates as the brick sits in the open air, it keeps absorbing carbon dioxide during its service life. Independent verification by EPD Hub found the company's N10 brick to be carbon negative across its full life cycle, absorbing in the region of 0.178 kg of CO₂ per brick — a real number, and one worth knowing the size of before anyone reaches for the phrase "buildings as carbon sinks". At end of life the bricks can be crushed and remade, or returned to soil to grow things in, which concrete cannot be.

The commercial half of the story belongs to Lei Zhang, a structural engineer of eighteen years who was handed a finished design in 2020 and asked to make it net zero. He went looking for a way to do it and concluded the technology did not exist. Later, calculating embodied carbon for a building on HS2, he found a single structure carrying more than 400 tonnes of CO₂ — a figure he had not expected and could not design away. He had read about Part Z, an industry-drafted proposal for whole-life carbon reporting, and assumed regulation was coming. It still has not. The episode carries a short correction on that point: embodied carbon remains unregulated in the UK, which arguably sharpens his argument rather than weakening it.

The most bracing passage comes from Cecilia Pesce, whose background is in the chemistry of conserving cultural heritage. Asked what the past can teach sustainable building, she gives the expected answer — raw earth is an ancient technique, dismissed as rudimentary, and it works — and then volunteers the opposite case. Traditional lime production is badly incompatible with modern carbon targets: you burn fuel to heat limestone, and the limestone itself releases CO₂ as it breaks down. The old ways are not automatically the wise ones, and the company's entire proposition rests on having replaced one of them.

Then there is the catch. Anna Simmons, who handles business support, is candid about the reception: real enthusiasm, and real scepticism, because when something sounds that good people go looking for the flaw. She does not claim the bricks are cheap. Some prospective customers tell her the price is outside their budget; others are pleasantly surprised. In an episode largely made of people describing their own company, that sentence does more for its credibility than any of the carbon figures.

The range that answers the objection: standard bricks, brick slips and frogged bricks, in colours that follow the soil or...

In the first of a three-part series, Jackie De Burca sits down with the two landscape architects behind Cork's Marina Park — Patrick McCabe of Redscape and Rani Ishar of Okra Landscape Architects — to unpack how a low-lying, formerly derelict 36-hectare site on the edge of Cork's South Docklands became one of the most ambitious pieces of public realm in modern Ireland.

Marina Park is often described as Ireland's first water park — not because of leisure or waves, but because water is the organising idea running through the whole design. The park is engineered to hold hours of stormwater when the River Lee is too high to drain into, and to release it back when the tide falls. Around that engineering sits a public space that hosts hurling finals at Páirc Uí Chaoimh, a promenade walked by more than ten thousand people at weekends, and a heritage trail reaching back to the 18th century.

This first episode is about how the park came to be. Patrick and Rani walk through the international competition Okra won in 2012, the multidisciplinary team that shaped the design, the fifteen-year phased delivery, the signature sinuous lines drawn from the river's own historic geography, the iconic red building preserved from the old showgrounds, and the layers of Cork history the park has quietly pulled back into public life.

In the next episode we get into the philosophy — living with water, and what Irish cities could learn from it. In the third, we look at what Marina Park has catalysed since it opened.

Landscape architect · Founder, Redscape

Irish-born, Netherlands-based, Patrick trained at University College Dublin and then took a design masters in the Netherlands. He's the founder and director of Redscape, working across regional-scale planning, parks, heritage and water management between Ireland and the Netherlands. He is part of Rivers 2040, an international study exploring how urban rivers could become central to regeneration.

Associate Architect · Okra Landscape Architects

Rani is an Associate Architect at Okra Landscape Architects, the Utrecht-based Dutch firm that led Marina Park's design. Okra's fifteen-year relationship with Cork began with the 2012 Marina Park competition and now extends to the North Docks, the South Docks and wider docklands regeneration. Rani focuses on integrated public-realm design for climate adaptation, urban naturalisation and healthy urban living.